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We revisit the the rare kaon decays $K\to \pi l^+l^-$ which are of interestspecially due to the recent measurements of the charged kaon decay spectra. Wecompute the contribution of the 27-plet to the decay amplitudes in one loopSU(3) Chiral Perturbation Theory. We estimate the resulting impact to be $\sim10%$ to the branching ratios of the charged kaon decays, and also noticeablyinfluence the shape of the spectra. With current values of the constants $G_8$associated with the octet and $G_{27}$ associated with the 27-plet, thecontribution of the latter pushes the spectrum in the correct direction for thecharged lepton spectra. We also discuss the impact for the neutral decay ratesand spectra.

The 27-plet contributions to the CP-conserving $K\rightarrow \pi l^+l^-$ decays